Localization of transverse waves in randomly layered media at oblique incidence

TL;DR

This paper studies how transverse waves localize in randomly layered media at oblique angles, revealing polarization-dependent effects and a stochastic Brewster angle where the medium becomes transparent.

Contribution

It introduces an approximate method for calculating localization length at oblique incidence, highlighting polarization effects and the stochastic Brewster phenomenon.

Findings

P-polarized waves have longer localization lengths than S-waves.

Localization length varies non-monotonically with incident angle for P-polarization.

A stochastic Brewster angle exists where the medium becomes transparent for certain angles.

Abstract

We investigate the oblique incidence of transverse waves on a randomly layered medium in the limit of strong disorder. An approximate method for calculating the inverse localization length based on the assumptions of zero energy flux and complete phase stochastization is presented. Two effects not found at normal incidence have been studied: dependence of the localization length on the polarization, and decrease of the localization length due to the internal reflections from layers with small refractive indexes. The inverse localization length (attenuation rate) for P-polarized radiation is shown to be always smaller than that of S-waves, which is to say that long enough randomly layered sample polarizes transmitted radiation. The localization length for P-polarization depends non-monotonically on the angle of propagation, and under certain conditions turns to infinity at some angle, which means that typical (non-resonant) random realizations become transparent at this angle of incidence (stochastic Brewster effect).